TOC  |    Herbal Medicine    

Herbal Medicine                                            
REF:  http://www.intelihealth.com/IH/ihtIH/WSIHW000/8513/31402.html    

Cranberry (Vaccinium macrocarpon)   

Be aware that the U. S. Food and Drug Administration does not strictly regulate herbs and dietary supplements. There is no guarantee of strength, purity or safety of products containing or claiming to contain valerian. Decisions to use herbs or supplements should be carefully considered. Individuals using prescription drugs should discuss taking herbs or supplements with their pharmacists or health care providers before starting.

Evidence    

Urinary tract infection prevention

Multiple studies report that taking cranberry juice or pills by mouth may help prevent urinary tract infections and may particularly work against the bacteria Escherichia coli. Side effects are common in human trials. A recent meta-analysis concludes that there is some evidence from two good-quality randomized clinical trials that cranberry juice may decrease the number of symptomatic urinary tract infections over a 12-month period in women. If it is effective for other groups such as children and elderly men and women is not clear. The large number of dropouts/withdrawals from some of the trials indicates that cranberry juice may not be acceptable over long periods of time. In addition, it is not clear what is the optimum dosage or method of administration (for example, juice or tablets). Further properly designed trials with relevant outcomes are needed.

Urinary tract infection treatment

Studies have found that cranberry is not helpful for treating urinary tract infections once they have already started. It may be used as an adjunct to conventional therapy. With the emergence of antibiotic resistant organisms, alternative antibiotic treatment is being sought out. Cranberry is a phytomedicine that has been proven effective for urinary tract infections and may prove as a promising alternative.

Other

Cranberry has been studied for several other purposes, but without enough scientific evidence to make any recommendations. These areas of study include prevention of Helicobacter pylori infections (which may occur in the stomach or early part of the intestine and may cause ulcers), viral or fungal infections, kidney stones, dental plaque, cancer, urine acidification, care of urostomy sites and reduction of odor from urinary incontinence. Early research suggests cranberry juice is not an effective treatment in the prevention of urinary tract infections caused by neurogenic bladder or in the treatment of urinary symptoms from prostate cancer radiation therapy.

Unproven Uses     

Cranberry has been suggested for many other uses, based on tradition or on scientific theories. However, these uses have not been thoroughly studied in humans, and there is limited scientific evidence about safety or effectiveness. Some of these suggested uses are for conditions that are potentially serious and even life-threatening. You should consult a health care provider before using cranberry for any unproven use.

Anorexia Antibacterial Antifungal, Candida albicans Antioxidant Bladder conditions Bladder infections Blood disorders Cancer Chronic urinary tract infections Decontamination of meats Gallbladder disease

Improved brain function Liver disorders Plaque Prostate cancer Recurrent cystitis Rheumatoid arthritis Scurvy Stomach ailments Vitamin B-12 absorption Vomiting Wound care

Potential Dangers     

Allergies

Side Effects

• Few side effects have been reported with cranberry when used at the recommended doses. At higher doses, the most common complaints include stomach discomfort and diarrhea. Cranberry should not be used instead of antibiotics for the treatment of urinary tract infections. Some experts recommend limiting the use of cranberry by people with certain types of kidney stones. Individuals with diabetes should drink sugar-free cranberry juice to avoid excessive sugar intake. One study showed the occurrence of vaginal yeast infections in women who consume cranberry juice.

Pregnancy And Breast-Feeding

• Cranberry cannot be recommended during pregnancy or breast-feeding in amounts greater than usually found in foods. Many experts believe that cranberry is safe, but currently there is not enough information. Be aware that many tinctures contain high levels of alcohol and should be avoided during pregnancy.

Interactions   

Interactions with drugs, supplements and other herbs have not been thoroughly studied. The interactions listed below have been reported in scientific publications. If you are taking prescription drugs, speak with your health care provider or pharmacist before using herbs or dietary supplements.

Interactions With Drugs

• Cranberry can increase vitamin B-12 absorption in people taking proton-pump inhibitors, such as esomeprazole (Nexium). Because of its acidity, cranberry juice may, in theory, increase the effects of antibiotics, affect how the kidneys remove certain drugs from the body and counteract antacids. The high alcohol content in some cranberry tinctures may lead to vomiting if used with the drug disulfiram (Antabuse) or metronidazole (Flagyl).
• Studies have shown that taking the prescription blood thinner warfarin and cranberry products at the same time can elevate the international normalized ratio for anticoagulant monitoring, which could increase the risk of bleeding.

Interactions With Herbs And Dietary Supplements

• In theory, cranberry juice may affect how the kidneys remove certain herbs and dietary supplements from the body. Theoretically, cranberry products may increase the risk of bleeding in people taking other herbs or supplements like garlic or danshen. Check with your health care provider before using other herbs and dietary supplements with cranberry.

Dosing    

The doses listed below are based on scientific research, publications or traditional use. Because most herbs and supplements have not been thoroughly studied or monitored, safety and effectiveness may not have been proven. Brands may be made differently, with variable ingredients even within the same brand. Combination products often contain small amounts of each ingredient and may not be effective. Appropriate dosing should be discussed with a health care provider before starting therapy; always read the recommendations on a product's label. The dosing for unproven uses should be approached cautiously, because scientific information is limited in these areas.

For Urinary Tract Infection Prevention  Adults (Aged 18 Or Older)

• Cranberry juice cocktail (sweetened): A dose of 300 milliliters (10 ounces) per day by mouth has been used.
• 100 Percent cranberry juice (unsweetened): A dose of 15 to 30 milliliters per day has been taken by mouth. One study suggests that 500 milliliters of cranberry juice with 1,500 milliliters of water is sufficient in helping prevent the formation of oxalate kidney stones.
• Capsules (of cranberry juice powder): Between one and six 300- to 400-milligram capsules twice daily by mouth have been taken with water one hour before or two hours after meals.
• Frozen juice concentrate: A dose of 1.5 ounces twice daily has been by mouth.
• Tincture: A dose of four to five milliliters three times daily has been by mouth.

Children (Younger Than 18):  The dosing and safety of cranberry have not been studied thoroughly in children, and it is recommended that you discuss doses with your child's health care provider before starting therapy. The amount of cranberry usually found in foods is often assumed to be safe. One study used doses of 300 milliliters of cranberry juice daily for three months in children aged 2 to 18 years; however, there is not enough scientific support or safety data for this dosage.

Summary     

Although cranberry has been suggested for many conditions, the best evidence supports its use for preventing urinary tract infections. Cranberry has not been proven effective for any other health conditions. People taking proton-pump inhibitors, antacids, antibiotics and drugs removed from the body by the kidneys should consult their health care provider before taking cranberry in amounts greater than usually found in foods. People with diabetes should be aware that cranberry juice may be high in sugar; sugar-free cranberry juice products are available. Remember that tinctures may contain large amounts of alcohol and may cause nausea and vomiting if taken with the drug disulfiram or metronidazole. Consult your health care provider if you experience side effects.

The information in this monograph was prepared by the professional staff at Natural Standard, based on thorough systematic review of scientific evidence. The material was reviewed by the Faculty of the Harvard Medical School with final editing approved by Natural Standard.

Resources     

Selected Scientific Studies: Cranberry

• Natural Standard reviewed more than 220 articles to prepare the professional monograph from which this version was created.

Some of the more recent studies are listed below:

Last updated June 02, 2005